Permutations Problems
12 Permutations problems on LeetCode, a Backtracking interview pattern, ranked by importance (how often it comes up in real interviews). Difficulty (ELO) and importance shown per problem.
| # | PROBLEM | DIFF | ELO | IMP | PATTERNS |
|---|---|---|---|---|---|
| 1 | Permutations | Easy | 1244 | 92 | Frequency Counting / Hash Map Lookup |
| 2 | Permutations II | Medium | 1408 | 82 | Frequency Counting / Hash Map Lookup · Sorting + Comparison |
| 3 | Letter Tile Possibilities | Medium | 1741 | 72 | Frequency Counting / Hash Map Lookup |
| 4 | Permutations IIIPREMIUM | Easy | 1380 | 58 | Constraint Satisfaction (N-Queens) |
| 5 | Palindrome Permutation IIPREMIUM | Medium | 1558 | 50 | Frequency Counting / Hash Map Lookup |
MORE BACKTRACKING PATTERNS
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